Field of the Invention
The teachings in accordance with the exemplary embodiments of this present disclosure generally relate to a lens moving unit and a camera module having the same.
Background of the Related Art
In general, a camera module may include an optical system formed with an image sensor, a PCB (Printed Circuit Board) mounted with the image sensor configured to transmit an electric signal, an IR (Infrared) cut-off filter configured to cut off light of infrared region from the image sensor and at least one sheet of lens configured to transmit an image to the image sensor. At this time, the optical system may be installed with a lens moving unit configured to perform an auto focusing function and a hand shake correction function.
The lens moving unit may be variably formed and widely uses a voice coil unit motor. The voice coil unit motor is operated by an electric interaction between a magnet fixed to a housing and a coil unit wound on a periphery of a bobbin coupled to a lens barrel to perform an auto focusing function. An actuator module of voice coil motor method thus described is operated in a manner such that a vertically-moving bobbin is elastically supported by upper and bottom elastic members to reciprocally move to a direction parallel to an optical axis.
Although development of a lens moving unit is recently demanded to quickly grasp an optimal focusing position by receiving position information of a bobbin mounted with a lens in order to shorten an auto focusing time of a camera module, the lens moving unit may suffer, in terms of performance, from disadvantages of instability in electromagnetic force and eccentricity of a lens barrel due to magnetic force.